Fuel-injector for locomotive-stokers



V 'N. M. LOWER. FUELJNIECTOR FOR LDCOMOTIVE STOKERS,

" APPLICATION man AUG-19.1915.

1,868,272. mm Feb. 15,1921.

' 2 SHEETS'-SHEET1C N. LOWER. FUEL INJECIOR FOR LOCOMOTIVE STOKERS.

APPLICATION FILED AUG-19,1915.

1,368,272. Patented Eeb15,1921. F H3 7 2 SHEETS-SHEET 2. I

4 4 I 3f I -1-55355555-31-1-3 #1 K I. I?! a" L 2 2 a g "I gave E B I E II o. l--l--. V I L mp 10 forcibly injecting fuel into and distribut-NATHAN 1VL LOWER, F SCHENECTADY, NEW YORK, ASSIGNOR TOgLOCQMOTIVE STOKERCOMPANY, or! PITTSBURGH, PENNSYLVANIA.

PENNSYLVANIA,- A. CORPORATION OF FUEL-1N3 ECTOR FORLOCOMOTIVE-S'I'OKER$.

Specification of Letters Patent. Patented Fell), 15, 19,21.

, Original application file'zl october 16, 1912, Serial No. 726,108.Divided and this-application filed August 19,

1915. Serial To all whom it may concern:

Be it known that I, NATHAN M. LOWER, a citizen of the United States, anda resident of Schenectady, in the county of Sche: nectady and State ofNew York, have invented a new and useful Improvement in Fuel-Injectorsfor Locomotive-Stokers, of which the following is a specification.

This invention relates to Stoker mechanism, and particularly tomechanism for ing it inthe fire box. The object of the invention is toprovide improved mechanism of the type described which is eflicient inoperation, which is simple in construction and is not liable to easilyget out oforder, which is readily controlled and operated, which injectsthe fuel by a sudden impulse so as to deliver all of the charge to thefire box, and which scatters the fuel laterally so as to distribute ituniformly over the fire and cover its back corners and sidesas well asits central portion. Further objects of the invention are in partobvious and in part will appear more in detail hereinafter. Theinvention comprises the construction and arrangement of partshereinafter described and claimed.

In the drawings, Figure 1 represents a longitudinal elevation throughone form of apparatus embodying the invention; Fig. 2

is a sectional plan view, on a, larger scale, on the line 2-2, Fig. 1;Fig. 3 is a cross section on the line 3--3, Fig. 2; Fig. 4 is a detailview of certain valve mechanism; Fig. 5 is a sectional view through thevalve mechanism for supplying fluid pressure to 'the plunger cylinder;Fig. 6 1s a sectional view, taken on the line 6-6 of Fig. 7, of meansfor controlling fluid pressure of the valve mechanism, on an enlargedscale; and Fig. 7 is a sectional elevation showing a portion of one formof locomotive stokcr mechanism to which the invention may be applied.

This application is a division of my prior application for locomotivestoker, filed Octobei 16, 1912, Serial No. 726,108, and claims only themechanism for 'feeding or injecting the fuel into and distributing it inthe fire box. The furnace and the me ger mechanism for delivering thefuel 'to t'he feeding or injecting device form no part Referring to thedrawings, 1 illustrates.

the front wall of the fire box, which may be. the fire box of thelocomotive or any fur nace to which the invention is applied. suitablenumber of fuel injecting devices 1 may be applied to the firebox, eithera single injector at the center of the wall 1 or two or more thereoflocated above or below;

the usual hand firing door or doors (not) .1

shown), as will be readily understood.

Each fuel injeotorcomprises a hollow cylindrical casing 2 provided, witha laterally.-

extending portion 3 through which the fuel.

is delivered to the casing in any suitablemanneigeither .by hand througha doorway closed by a cover 4:, or automatically through an opening 5communicating with the fuel transfer and conveying mechanism leadingfrom the ply bin. v

The fuel falls in front of the head 6 of a. hollow piston 7 which slidesin the casing tender or other fuel sup- 2 and is forcibly impelledtoward the fire box to inject a charge of. fuel; thereinto. Said head isprovided with a forwardly ex:

tending scoop or shovel member 9 traveling I ceives the fuel and carriesit-during the for in the bottom of the casing 2 and which rewardmovement of the-piston. The casing 2 is provided with a passage 10communicating with a source of fluid pressure, such as a steam orcompressed air supply pipe 11. a bald passage, at its other end,communicates with a space 12, within a hollow cylin der or pipe 13attached at its outerend to a cap: or cover 14 closing the outer endofJ-the casing 2 and provided at its inner end with a circular head orwall 15 provided with apacking 16 on which the cylindrical piston 7travels. The head 6 of said piston, in its retracted position, seatsagainst an annular surface 17 at the outer end of the pipe 13 and head15, so as to restrictxthe areaof the back of the head 6 against whichthe fluid pressure is effective in initiating the piston :troke. Thepiston is provided at its 'outer end with a follower head I 18,.,.which"" is shaped to fit neatly into an'annular space and prevent aheavy blow or knock.

bearing against the outer face of the head (5, so that pressure isconfined against a limitedt irea at the center of the piston, to startthe piston stroke, but as soon as the piston has moved forwardlyslightly the fluid. pressure is admitted to a larger area on the outerface of said piston, whereupon said piston is moved forwardly with asudden impu-lse to the end of its stroke, or until the follower head 18reaches the cushioning space 19. The passage 10, the hollow space in thecap or head 14, and the space 12 within the tube 13 form in effect areservoir in immediate proximity to the piston or plunger, so that assoon as the latter begins to move, the expansive power of the fluidpressure in this reservoir produces a very rapid movement of the piston.

' 'Within the hollow space 12 is located a tension spring 20 connectedat one end to the'head 6 and at its opposite end to a. plug 21 threadedon an adjusting screw 22 extending through the wall of the cap 14;

This spring returns the piston and scoop to initial position afterdelivery of each charge of fuel to the fire box, it being understoodthat at thistime the space 12 is open to exhaust through the valvemechanism controlling the supply of compressed air to the device.

To assist in distributing the fuel lateraliy over the fire bed thepiston is provided with one or more laterally movable members, shown asa pair of wings orvanes 25 pivotally mounted upon short shafts2(3-cai'ried by the scoop or shovel 9 and located at opposite sides ofthe central longitudinal axis of said shovel. Thes'ewings or vanes areprovided with outwardly extending short arms 27 whose ends travel ingrooves or slots 28 in the side walls of the :asing 2, the ends of saidgrooves or slots, marked 28, 28", forming abutments to engage the arms27 and move the wings or vanes laterally. The vanes 25 are curved, asshown in Fig. 2, thus providing curved fuel impelling facesfwhich havethe effect (when said vanes arrapidly oscillated) of preventing the fuelf gom sliding endwise of the vanes, but. impeding aconsiderable part ofthe fuel sidewise andjdistributing-it with a sweeping motion along thesides of the fire box, from the front to the rear thereof.

During the delivery of the fuel to the injecting device the wings orvane? 25 occupy the positions shown in full lines in Fig. 2,

'and all or a portion of said fuel is delivered to the scoop .or shovel9 on the outside of said. wings or vanes.

At the end of each inward stroke of the piston the vanes 27 engage theabutments 28 and oscillate said vanes outwardly around their verticalaxes, thereby impelling a portion of the fuel outwardly and distributingit to the sides of the fire box. The outward swinging movement of thevanes 25 is stopped by said vanes striking the ends of the side portionsof the shovel 9, which latter therefore serve as limiting stops for thevanes to prevent them from swinging around far enough to strikethe endwall of the fire box. The inward motion of the piston also throws thefuel inwardly into the fire box, so that some of it at least isdelivered to the far back corners of the fire box. 011 the returnmovement of the piston the wings or vanes 25 engage the inner end of thecasing 2, or thewall of the tire box, which oscillates s'aid wings orvanes to their inner positions, the movement being completed by theengagement of the arms 27 with the inner abutments 28". In some cases itmay also be advisable to assist in lateral distribution of the fuel bymeans of a jet or jets of fluid pressure. For this purpose, asillustrated, the Head (3 of the piston is provided with a longitudinalpassage 30 in which is located a valve 31 controlling a side passage 32in the wall 'ofa pipe or tube 33 extending to the inner end of the scoopor shovel 9 and having lateral branches 3% arranged to deliver twolateral of fluid pressure in opposite directions. The pipe or tube 33 isshown as an integral 'boss or enlargement of the .scoop or shovel 9.

As soon as the piston head (3 leaves its seat 17 fluid pressure expandsinto the space between. the heads (3 and 15 and enters the passage 30,traveling through the side passage 32 beyond the valve 31 and beingdischar ed through the side branch passages 3.4;. The valve mechanismfor controlling the supply of fluid pressure to the injector is usuallyarranged to vary the rate of 'supply of the -fluid during differentstrokes. so as to produce lightand heavy impulses of the piston. thesupply of fluid pressure. is slower, and is insuflicient to force thevalve 31 to its seat against the action of its spring 35, which normallyholds the valve against a stop 36. ()n heavy strokes of the piston,however,

. when a larger supply of fluid pressure is de livered, to the pistonthe higher pressure forces said valve to its seat, as shown in Fig. 1,which closes the end of the passage 32 and cuts off the steam supply tothe pipe 33. The fluid pressure supply is therefore eflective only onlight strokes of the piston and is valuable indistributing the fuel tothe sides and at the front of the fire box.

One form of suitable. valve mechanism for controlling the fluid pressureto the injector so as to produce light and heavy strokes. is illustratedand described in my prior ap plication Serial No 7265108 and is illustrated, described and claimed in my co-pending application Serial No, 46336 filed si multaneous of said up tion serial No. TBS-J08.

Said valve mechanism, and the control mechanism therefor are illustratedin Figs. 5, 6 and 7. This "alve mechanism comprises a hollow casing 4-2which may be connected to or continuous with the casing 2. In the casing42 is a chamber 43 in which is slidably mounted av'alve member having astem 44 and two healdt' 45 each provided with a small through leak port46. Pressure is supplied to the chamber 43 ,between the heads 45tl'iroughthe port or open ing 11, from which it passes to the passage 10through two ports or openings, marked 48 and 48 respectively,communicating with passages leading to the passage 10. The port 48 ispreferably smaller than the port 48. The outer ends of the chamber 43are closed by threaded plugs 49 having openings 50 therein, one of saidopenings communicating with a pipe 51'and the other with'a pipe 51. Thesliding valve mechanism is 'normally held in central position by twocompression springs 52 located between the plugs 49 and the outer endsof thepiston heads 45, and the tension of which springs may be adjustedby screwing the plugs 49 in or out as required.

Each head acts as a valve to cover or uncover its port 48 or 48, and theoutward movement of said heads may be controlled by threaded stopsprovided with graduated heads 54 cooperating with pointers 55 toindicate the position of said stops: By

adjusting these stops the heads 45 will un cover the ports '48 and 48more or less and thus enable the intensity of the different strokes ofthe piston to be varied.

"When the valve stem 44 and heads mov to the left in Fig. 5, the smallport or opening 48 is uncovered, which allows pressure to flow from theinlet 11 to the passage 10 and thence to the fuel injecting piston, butthe fluid pressure supply is restricted so that only a light stroke isproduced. l l 'hen the valve head and stem move in the opposite ydirection, or to the right, port 48 is uncovered, which allows a morerapid supply. of fluid pressure with 'a correspondingly heavy stroke.

The movement of the valve stem 44 and heads 4-5 may be controlled orproduced in any suitable :rmumer but preferably by unbalancing thepressures on the outer faces of the two heads, either by diminishing thepressure effective on one head or by increasing that on the other. 6shows one arrangement of mechanism suitable for this purpose, saidmechanism comprising a cas in-g 57 preferably open to the atmospherethrough a port 52', in which is located l herewith and. being a divisiona rotary shaft 58 carrying a worm 59 connected to a worm Wheel 60, theshaft 60 of which is journaled in oneside of the casing. One side of thecasing is provided with an inwardly extending boss 61 contact ing withone side face of the worm wheel 60 and provided with athrough bore 61communicating with a pipe connected to the space on the outer surface ofone of the heads 45, and which may for example be the pipe 51. The otherside of the casing 57 is provided with a rotatably adjustable member 62whose inner end; contacts with haust the chambers 0n the outer faces ofthe heads 45. v c

When the passage 63 is out of register with both of the passages 61 and62*, communication to the chambers on the outer faces of the heads 45 isclosed except through the leak ports 46, so that pressure will build upin said chambers from the inlet 11. Each piston head is therefore subjected to the pressure of a spring and to 7 equal pressure on itsopposite faces, so that the valve mechanism shown in Fig. 5 lies inbentral or neutral position. Wheneverthe passage 63 in the worm wheelcomes opposite one of the passages 61 'or 62 the chamber on the outsideof the corresponding piston head is opened to exhaust, whichalloivs thepressure on the inner .face' of said head to become effective and movethe valve, thus opening one or the other of the ports 48, 48 to thesource of pressure. As soon as the passage 63 moves away from itsopening the pressure again builds up behind the head 45 and moves thevalve mechanism back to normal position. The fuel injecting piston 6then returns to normal position under the influence of the spring 20,the pressure behind said p-iston being exhausted through a passage 64 inone of the pistons 45, which communi rates in normal position of thevalve mechanism with a channel in the easing leading to' an exhaustopening 65.

The rotary member 62 is held against its face of the worm wheel 60 byacompression spring 66, which produces a tight seal between said wormwheel at the open ends of the boss 61 and member 62 and prevents extherotatable member 62 is diametrically opi 'posite the opening '61" in theboss 61, so that successive strokes of the fuel injecting piston areproduced at uniform or regular in- ,tervals. Member 62, however, isprovided said member in the proper direction the time interval precedinga light piston stroke may be made shorter than that preceding a heavystroke or vice versa. This enables a larger quantity of fuel to becollected on the piston scoop before either the light or heavy stroke,

so that a larger proportion of the fuel may Ibo fed either to the frontor rear of the fire The controlling device shown in Fig. 6 for the valvemechanism which operates the fuel injection piston is operated by arotary shaft 58, which may be any suitable shaft on the locomotive. Itmay be hand-operated or operated by any suitable mechanism, but isespecially adapted for connection to a locomotive stoker-mechanismoperated by a rotary engine. For example, Fig. 7-sh0ws locomotive stokermechanism ofthe same form illustrated in my prior application re ferredto, said mechanism being operated by a rotary engine which drives therotary shaft 58 passing through the casing 57 of the controlling device.Said shaft is con nected to a longitudinally extending spiral conveyor71 which conveys the fuel from the locomotive tender (not shown) to aposition beneath tivo upstanding conduits 73 through which the fuel iselevated to the fuel inlets 5 of the fuel injecting cylinders 1. Theelevating mechanism. comprises reciprocating bars provided with foldingvanes, and is operatedby a connection to the shaft 58, in the samemanner as insaid prior application, and therefore requires no furtherdescription.

The mechanism described is of simple construction and can be used withany type of stoker mechanism. It produces a thorough distribution offuel in the fire box and promotes uniform consumption so that a maximumnumber of heat units are obtained from the fuel. It is automatic inoperation so that no attention is required on the part of the operator,and is not liable to easily get out of order. I

What I claim is 1. Fuel injecting mechanism for stoker mechanism,comprising a broad vertically standing vane mounted to oscillate about avertical axis and having its free end bent to provide a curved fuelimpelling face, and

mechanism for imparting rapid oscillatory movement to said vane todistribute the fuel over the surface of the fire.

2. Fuel injecting mechanism for stoker mechanism, comprisinga pair ofoppositely tribute the fuel over the surface of the fire.

3. Fuel injecting means comprising a reciprocable shovel, a vanepivotally mounted on the shovel for lateral oscillation over the floorthereof, and means for causing outward movement of the vane on theadvance .stroke of the shovel.

4. Fuel injecting means comprising a reciprocable shovel, a pair ofvanes pivotally mounted on the shovel for lateral oscillation over thefloor thereof, and-means for causing outward movement of the vanes onthe advance stroke of the shovel.

Fuel injecting means comprising a reciprocable s'hovel, a pair of vanespivotally mounted on the shovel for lateral oscillation over the floorthereof, means for causing outward movement of the vanes on the advancestroke of the shovel, and means for causing inward movement of the vaneson the back stroke of the shovel.

6. F ucl in ecting means comprising a reciprocable shovel, a dischargenozzle having upstanding, side abut'ments adjacent its inner and outerends, a shovel reciprocable in. the nozzle, a pair of laterallyoscillatable vanes carried by. the shovel and movable over its floor,each vane having a lateral arm engageable with a pair of the abutments.

7.. Fuel injecting means comprising a reciprocable shovel, a pair ofcurved vanes pivotally mounted on the shovel for lateral oscillationover the floor thereof, and means for causing outward movement of thevanes on the advance stroke of the shovel.

8. In a stoker mechanism, in con'ibination, a feed plate, means fordelivering fuel-to the plate, a curved vane pivotally mounted over theplate on a vertical axis, and means for turning the vane on its pivot tosweep the fuel from the plate and throw it into the fire-box of thefurnace.

9. In a stoker mechanism, in combination, a feed plate, means fordelivering fuel to the plate, a vane pivoted on a vertical axis over theplate, and means for turning the vane on its pivot to sweep the fuelfrom the plate, such vane having its outer end curved whereby the fuelis thrown laterally and baclnvardly.

10. Fuel injecting mechanism for stoker with 1,ees,272

move the vane about. its axis to distribute the fuel laterally, theopposite end of said slot being arranged to engage saidarni upon thereturn movement of said plunger to re turn the vane to its initialposition.

l1.'-Fuel injecting mechanism for stoker mechanism, comprising acylinder provided slots and having a power-operated plunger thereinforimpelling fuel toward 7 a fire box, vanes-pivoted to said plunger,having arms projecting into the slots in the cylinder, the ends of saidslots being arranged to engage the arms on the vanes as the plungerreaches the end ofits forward stroke to move the vanes about theirpivots to distribute the fuel laterally, the opposite ends of the slotsengaging said arms upon the. return movement of the plunger to returnthe vanes to theirinitial position.

12. Fuel injecting mechanism, comprising acylinder, a power-actuatedshovel therein, a vane pivotally mounted on the shovel for lateraloscillation over the floor thereof, a stationary abutment, and an arm onsaid vane arranged to engage said abutment as the. plunger moves forwardto thereby swing the vane on its axis to scatter the fuel laterally overthe fire. I v

13. Fuel injecting mechanism, com rising a cylinder, a power-actuatedshovel t erein, a vane pivotally mounted on the shovel for lateraloscillation over the floor thereof,

an arm on said vane, a fixed abutment arranged to be engaged by said armas the plunger moves forward to thereby oscillate the vane and-scatterthe fuel over the fire, and a second abutment arranged to be engaged bythe said arm on the return movement of the shovel to return the vane toits initial position.

14. Fuel injecting mechanism, comprising a. cylinder, a power-actuatedshovel therein, a pair of vanes pivotally mounted on the shoved forlateral oscillation over the floor thereof, and means for oscillatingsaid vanes .on their axes on the advance stroke of the shovel. j

15. Fuel injecting mechanism, comprising a cylinder, a power-actuatedshovel therein for impelling fuel toward a fire box, a pair of broadvertically standing vanes pivotally mounted on said shovel on verticalaxes, an arm on each of said vanes, a'butments arranged to engage saidarms on the forward movement of the shovel and swing the vanes toscatter the fuel laterally over the fire, and abutments for engagingsaid arms upon the return movement of the shovel to return the vanes totheir initial positions.

16. Fuel injecting mechanism, comprising a cylinder, afiuid pressureoperated fuel injecting shovel therein,'and means carried by said shoveland arranged to produce lateral jets of. fluid. thereacross when theshovel moves inwardly, to distribute the fuel laterally.

17. Fuel injecting mechanism for stoker fluid supply to plunger strokesof varying intensity, and means on said plunger for producing lateraljets of motive fluid to distribute the fuel laterally.

18. Fuel injecting mechanism for stoker mechanism, comprising acylinder, a fluid pressure operated fuel injecting piston movabletherein, a scoop or shovel carried by said piston and arranged toreceive fuel, and means on said scoop or shovel by which lateral jets offluid are produced as the piston moves forwardly to thereby" distributethe fuel laterally to tlie sides of the fire box.

19. Fuel injecting mechanism for stoker mechanism, comprising acylinder, a fluid pressure operated fuel injecting plunger therein,means for:-s ontr0lling the motive fluid supply to the plunger toproduce plunger strokes of varying intensity, and means on the plungerfor producing lateral jets of motive fluid upon light strokes of thepiston to distribute the fuel laterally.

20. Fuel injecting mechanism for stoker mechanism, comprising acylinder, a fluid pressure operated fuel injecting plunger therein,means for controlling the motive fluid supply to the plunger to produceplunger strokes of varying intensity, means on the plunger by whichlateral jets of motive fluid are produced for distributing the fuellaterally, means on the plunger for venting the motive fluid in lateraljets to distribute the fuel laterally, and means for preventing saidfluid being vented when the piston makes a heavy stroke.

21. Fuel injecting mechanism for stoker mechanism, comprising a cylinderhaving .a fluid pressure operated fuel injecting plunger therein, .meansfor controlling the motive fluid to said plunger to cause strokes ofvarying intensity, means by whichthe motive fluid for the plungerassists in the lateral distribution of the fuel, and valve mechanism forpreventing the motive fluid bein' so used when it is bein su lied insuch quantities as to cause a heavy stroke of the plunger. l l

22. Fuel injecting mechanism for stoker mechanism, comprising apower-operated plunger for impelling fuel toward a fire box, means fordistributing the fuel latmechanical means for distributing the fuellaterally as the plunger reaches the end of its stroke, and fluidpressure means for assisting in the lateral distribution of the fuel.

24. Fuel injecting mechanism for stoker mechanism, comprising apower-operated plunger for impelling fuel towarda fire box, mechanicalmeans for distributing the fuel laterally toward the end of the plungerstroke, and fluid pressure means for distributing the fuel laterallytoward the end of light plunger strokes.

25. Fuel injecting mechanism for stoker mechanism, comprising apower-operated plunger for iinpelling fuel toward a fire box, mechanicalmeans for distributing the fuel laterally toward the end of the plungerstroke, fluid pressure means for assisting in the lateral distributionof the fuel, and means for preventing operation of the fluid pressuredistributing means when the piston makes heavy strokes.

26. Fuel injecting mechanism for stoker mechanism, comprising apower-operated plunger, means independent of the plunger operating meansfor distributing the fuel laterally as the plunger reaches the end ofits stroke, and additional means for dis trihuting the fuel laterallyunder lignt pis ton strokes.

27. Fuel injecting mechanism for stoker mechanism, comprising a fluidpressure op erated plunger for iinpelling fuel toward a fire hox, meansfor regulating the supply of motive fluid to said plunger to causestrokes of varying intensity, means inde pendent of the plungeroperating means for distributing the fuel laterally as the plungerreaches the end of its stroke, and fluid pressure operated means forassisting in the lateral distribution of the fuel when fluid pressure issupplied to said plunger to cause a light stroke thereof.

28. Fuel injecting mechanism for stoker mechanism, comprising a fluidpressure operated plunger for impelling fuel toward a tire box, meansfor controlling the motive fluid to said plunger to cause strokes ofvarying intensity,mechanical means on said plunger for distributing thefuel laterally toward the end of the plunger stroke, means by which themotive fluid for the plunger assists in the lateral distribution of thefuel, and valve mechanism for preventing the molivc lluid being so usedwhen it is supplied in such quantities as to cause a heavy stroke of thepiston.

29. Fuel injecting mechanism for stoker mechanism, comprising afluid-pressure operated 'ilunger for impelling fuel toward a fire box,mechanical means on said plunger independent of the plunger operatingmechanism for distributing the fuel laterally as the plunger reaches theend of its stroke, means for venting the plunger operating 30. Fuelinjecting mechanism for automatic stokers, comprising a cylinder, areciprocating injecting plunger having a rearward extension guided insaid cylinder, a spring coaxial with and inclosed in said plungerextension and arranged to retract.

said plunger, and means for supplying fluid pressure to advance saidplunger.

31. Fuel injecting mechanism for automatic stoker, comprlsing, incombination, a cylinder, a reciprocating injecting plunger having arearward extension guided in said cylinder, a fixed tubular stem on theaxis of said cylinder and its forward end fitting within the tubularplunger extension, a plunger retracting spring within said fixed tubularstem, and means for supplying fluid pressure .to advance said plunger.

32. Fuel injecting mechanism for automatic stokers, comprising areciprocating fluid actuated motor, the moving part of said motorconstituting an ejecting plunger, means for admitting fluid pressure toadvance the plunger, and a spring housed within the motor and connectingthe'movable and stationary parts thereof for retracting the plunger.

33. Fuel injecting mechanism for automatic stokers, comprising incombination, a cylinder, a reciprocating injecting plunger having arearward extension guided in said cylinder, a fixed tubular stem on theaxis of said cylinder and its forward end fitting within the plungerextension, a plunger retracting spring within said tubular stem, andmeans for supplying 'fiuid pressure through said tubular stem.

34:. Fuel injecting mechanism for automatic stokers comprising, incombination, a fuel injecting plunger, fluid pressure means arranged toadvance said plunger suddenly,i-and a spring acted upon when saidplunger advances and arranged to retract the same.

Fuel injecting mechanism for automatic stokers comprising, incombination, a, cylinder, a reciprocating injecting plunger in saidcylinder, and a fluid inlet coaxial with cylinder and arranged to admitfluid initially to a, restricted area of said plunger and to a largerarea of said plunger after it has moved slightly, whereby said plungeris advanced suddenly. t

36. Fuel in ecting mechanism for automatic stokers comprising, incombination, a

cylinder, a reciprocating injecting plunger j in said cylinder, areservoir for a pressure fluid back of said plunger and in immediateproximity thereto, and an inlet from said reservoir to said cylinderarranged to admit fluid initially to a restricted area of adapted-t0traverse said receptacle between said plunger and to a larger area ofsaid plunger after it has moved slightly, Whereby said plunger isadvanced suddenly.

37. In a mechanical stoker, the combination of a receptacle into Whichfuel is demy hand. livered, a fuel carrying and throwing shove1 suremeans for impelling said shovel forwardly, and mechanical means forreturnmg the sald shovel to initial posltlon.

NATHAN M. LOWER.

positions in rear and in front of the avenue WVitnesses: of fueldelivery thereto, the said shovel be- CLYDE J. MQCURD ing adapted topick up and carry a charge THOS. OARMEB.

of fuel in its forward traverse, fluid pres In testimony whereof, I havehereunto set

